#flex(@direction, @items, @content) {
  display: flex;
  flex-direction: @direction;
  align-items: @items;
  justify-content: @content;
}
#flex-center(@direction, @content) {
  display: flex;
  flex-direction: @direction;
  align-items: center;
  justify-content: @content;
}
#flex-start(@direction, @content) {
  display: flex;
  flex-direction: @direction;
  align-items: flex-start;
  justify-content: @content;
}
#flex-end(@direction) {
  display: flex;
  flex-direction: @direction;
  align-items: flex-end;
  justify-content: flex-end;
}